1. Field of the Invention
The invention relates to high-frequency power amplifiers and operational parameters thereof.
2. Discussion of the Background
In the operation of high-frequency power amplifiers, for example, transistor power output stages of variable-frequency shortwave transmitters, it is necessary to determine and monitor various operational parameters, in particular, the matching of the load and the power. Various analog arrangements for this purpose are known from DE 27 10 752 A1 and respectively DE 39 18 159 A1. They have in common the fact that, for the determination of the operational parameters on the connecting line between the power amplifier and the antenna, directional couplers are used, and the calculation of the required operational parameters from the analog forward and respectively return voltage obtained by means of the directional coupler, which is proportional respectively to the forward and return wave on the connecting line, is implemented in an analog manner through correspondingly-complex analog circuits.